BP's Macondo oil well in the Gulf of Mexico finally "killed"

British oil giant, BP's blown out Macondo oil well in the Gulf of Mexico that created the biggest oil spill in US history, was "effectively killed," after pouring cement into the base of the well yesterday.

The US government said that BP's Macondo oil well is "effectively dead" after a final plug of cement was pumped in.

Thad Allen, the former coast guard admiral heading the government response to the spill said, "We can finally announce that the Macondo 252 well is effectively dead,".

US President Barack Obama welcomed the news and said that it was an "important milestone" and a critical step to ensure that the well has stopped leaking for ever.

It took the London-based oil giant five months to finally seal the leaking well after the Deepwater Horizon rig blew off on 20 April 2010 killing 11 people, and spewed 206 gallons of crude oil for nearly four months into the Gulf of Mexico before it was temporarily plugged on 15 July 2010.

''The MC252 well has been shut-in since July 15 and cementing operations in August, following the static kill, provided an effective cement plug in the well's casing. The relief well drilled by the DDIII drilling rig intercepted the annulus of the MC252 well on 15 September, followed by pumping of cement into the annulus on 17 September.